The Phasure NOS1 24/768 async USB D/A Converter again defines new standards. Not only the technical level is up to the extreme, but sonically it superceeds the original Phasure NOS1 by far. And that was already considered to be the best ...

Thinking about the explicit Sound Quality Control always incurred for by the XXHighEnd software, we are now greatly proud to anounce that all what could be done so indirectly in PC software before, can now be done directly in-DAC. A world's first once again !Although at this moment the DAC operates with the best sonic settings we could find, the firmware -which directly controls the hardware- is upgradeable in a whimp. And, like with XXHighEnd, more versions of it could be readily available on your computer, you picking the best sounding one. Changing the firmware is nothing more than reconnecting the DAC to the USB cable ...

With the knowledge of XXHighEnd and SQ control, together with the development experience of the original NOS1 - at last it was achieved that the software influence has been eliminated. SQ Controls in XXHighEnd won't do a thing to the sonic performance of the new NOS1, as won't different software sound different anymore (no Digital Sound Processing assumed to begin with).It is to be kept in mind though that the Phasure NOS1 async USB requires external filtering, so it is there where software still will matter. But, this is completely intentional (and is a form of DSP).

The NOS1 USB will work on any MAC just the same, but here too it is to be kept in mind that the external filtering is required for Redbook material. This is not the case for HiRes where all filtering just should be out of the way. On this matter the NOS1 does not contain any filtering of any kind, so its inherent impulse response (which is the mimimum of one sample long) will uniquely 100% show you what HiRes really brings.An optional Direct DSD/DSF (no conversion to PCM) input is due shortly as a user installable add-on board.

Where the original NOS1 already was fameous for its accuracy, the NOS1 USB dives into a whole new world of that. You will be shocked about the detail coming from your regular favorites. Basses will be basses like never before (including the original NOS1) and even at breaking in it will be noticed that no woman voice is able to go wrong ever anymore. The high frequency output has increased to a virtual crazy level, with the notice that here some break-in is needed (approx. 14 days).After that, distinguishing from live performers in your listening room will be the most tough. The sizes of instruments will show as never before. A piano sounds like a real piano. A sax can't go wrong. 60's recordings suddenly appear to be the best ever. The effortlessness of it all ...

Again assuming no preamp will be used (which is the explicit advice), a more than average good playback chain is assumed. This is related to the sheer speed of transients, and the requirement of the chain to be able to follow that. Without this, the sound may become somewhat aggressive.The NOS1 USB is targeted on the highest degree of audiophile music reproduction through loudspeakers, so most probably it will be allright - assuming all is aranged for to the best of knowledge anyway. Still, there is the usual 90 day money back guarantee just in case it isn't working out (Edit : see Phasure NOS1 Refund Model).However, for those experiencing problems in this realm, it is good to know that the beforementioned add-on board will contain an A/D section and with the help of the totally unique XXHighEnd analysis software (sadly not available for Mac) you will be able to create groundpaths for your chain with the least noise. See Measuring XXHighEnd from over two years back to get an idea of what this software can do, which sure is not only about eliminating noise. If you think cables matter, this will show you the truth without any doubts left.

Availability : Today (first unit ships July 20).This doesn't mean short delivery times though;We have very limited stock only, that coming from sample productions of the USB boards. This means a larger batch of that has to be produced first in order to be able to start assembling a sufficient amount of DAC units. It may take 4 weeks or more to obtain some free stock, but we may keep running behind forever.It is to be taken that the current stock already has been consumed by orders from the last few weeks because these orders were put on hold - knowing about this "upgrade" being due. These orders have obtained priority obviously.

Existing NOS1 users can fully upgrade to the NOS1 USB, but it will require to send over the DAC. In the mean time they might like to change the colour which is very well possible, but which will be relatively expensive, already because the DAC has to be fully de- and reassembled for that.After upgrading, the NOS1 USB will be as extensible with the options mentioned below in the Features list.

General Features Phasure NOS1 24/768 async USB :

(x) denotes a standard feature, contained in the price shown at the bottom

Fully upgradeable extremely robust Driver and Firmware for ASIO, WASAPI and Kernel Streaming. (x)Notice that XXHighEnd does *not* support ASIO at this time, but other playback software will.See below *) notations for planned near future software upgrades. The more * the lower the priority of development.

Meant for Windows PC and Apple Mac (32 and 64 bit Operaring Systems) (Mac at max 32/384 input at this time). Playback software is allowed to (and should) provide the filtering means (the DAC carries no destructive means of any sort). HiRes material is (and should be) passed 100% untouched. This means a truly "bit perfect" complete chain.At this time it is unknown what additional time it needs to develop the additional software extensions for the Mac.Edit August 22-2011 : By now it is clear that at least Audirvana does a fine job on the filtering.

Configuration hardware options/extensions available.See below +) notations for planned near future hardware upgrades. The more + the lower the priority of development.Notice that these are hardware extensions, and generally a not available extension at the moment of ordering/delivering will allow upgrading yourself by minimal soldering (if at all).

SPDIF Input.

SPDIF Output / Throughput.

i2s Input. +++)

SPDIF Input direct or SRC controlled. ***)

i2s Output. +++)

2ch USB/SPDIF converter only. +)This needs a special case.SPDIF output will be ultra low jitter, similar to the original Phasure NOS1.Can be combined with i2s Output (see above).

8 channel 24/384 operation. +++) ****)The interface is ready for this, the output stages of the D/A part are not at this time.The software development comprises in-driver XOver functions.4, 6 or 8 channel operation is user selectable.

Immune to playback software on the SQ department. (x)At last ...

The following is about hardware add-ons coming on a separate user-installable circuit board, which will be available in August 2011 :

DSD-128 (or -64) Input. **)Notice that this is about Direct DSD (not converted to PCM) and that at this moment XXHighEnd can not play Direct DSD yet. Other players can though.

24/192 2ch A/D conversion (recording).

Full system Noise Analysis. ***)This includes (later) upgradeable Driver software.Needs XXHighEnd and will also allow for the special XXHighEnd Analysis software (measure *any* difference in cables, software, etc. etc.).

Additional 2ch Oversampling (!) 24/192 D/A converter.

Specifications of the PCM D/A section in short :

All measurements at the end of a 2m cheap interlink, done with a dScopeIII digital analyser :

Frequency response 1 Hz to 384000 KHz (768KHz sample rate). Flat within 0.19dBr in the audio band (DC not sustainable).

Input of 16 or 32 bits for all Sample Rates (24 bit input is converted to 32 bits).

Output Sample Rates always equal the Input Sample Rates, but notice that in software (PC, XXHighEnd) each native “file” Input Rate can be upsampled to each accepted higher Output Rate (like 96000 to 384000 or 44100 to 176400 etc.) and next is output to the DAC. Output bit depth is 24 - or 16 bits when Input bit depth is 16 bits.

100% Filterless Non Oversampling design, using 8 x PCM1704U-K Burr Brown (Texas Instruments) multibit 24 bit D/A converter chips. Filtering for Redbook material to be applied in software (officially provided by XXHighEnd through Arc Prediction which supports all modes), or not using filtering at all (like for HiRes), at own choice.

Output level for Single Ended Mode (RCA) is 1.5VRMS (-3dBFS relative to normal Full Scale). Output level for Differential Mode (XLR) is 2.7VRMS (+3dBFS relative to normal Full Scale).

Output Impedance is 33 Ohm. It is the explicit advise to use the NOS1 without pre-amp and without analogue volume control for optimum results (long interlinks can be driven).

The Clock section consists of separate 44100 Hz and 48000 Hz base oscillators. The provided oscillators carry an overall jitter of better than 0.5ps and phase noise of better than 120dBc/Hz at 100Hz and better than 108dBc/Hz at 50Hz.

The net jitter should equal the fed jitter (of 0.5ps; there's nothing in the path from the oscillators to the D/A chips).

All terminals are official Neutrik.

Requirements PC : USB 2.0 interface.MAC : USB 2.0 interface.

Allowed USB cable length is 6 meters / 20' 7 meters / 23'.

USB is powered by an internal dedicated linear power supply.

Output terminals are provided for Single Ended (SE, RCA) as well as Differential (Balanced, XLR) by standard. No switches are in the signal path and no transformers are involved.

S/N ratio in-(audio)band is at –132dBFS at full scale (-0dBFS) differential (XLR) output.Out of band (from off 31000Hz and up to 96000Hz which is the measureable limit) this is better than –144dB, and at the limit of the analyser operating at 24 bit and 192KHz.For SE (RCA) output at –6dbFS (the maximum for the 1.5VRMS output) the noise is at –140dBFS or 134dB down. Here, the noise from off 31000Hz and up is at –144dBFS or 138dB down.

Mains related products for SE measure 17uVRMS at –121dBFS (measured at 50Hz mains). Notice this will be because of the pickup of noise of poor interlinks. Better interlinks will show better than 7 uVRMS at –128dBFS.Mains related products for Differential measure 2.2uVRMS at –139dBFS (measured with 50Hz mains).

SE (RCA) output measures in(-audio)band Unweighed 0.0018% THD+N at 16 or 24 bit input and an 1KHz test signal with a sample rate of 44100Hz and Arc Prediction filtered into 176400Hz. The THD+N from Differential (XLR) is beter than 0.0015% which is under the typicle specs of the D/A chips.Notice : This is measured at 24/192KHz sample rate because of analyser limits. But, the NOS1 USB is made for 24/768000(705600) input, which implies a theoretical factor of 4 better. Taking the Non Oversampling principle into account, it will be fair to calculate the 1KHz testsignal's THD to 0.00045% for RCA and to 0.000375% for XLR. This also counts for THD+N because the extrapolated result will still be above the noise floor.Further non-extrapolated results from 24/192000 measurement :The same 1KHz test signal measured unweighed over the total analyser’s useable range (0 – 96000Hz) shows a THD+N of better than 0.0035% (XLR).A-Weighed this is better than 0.0013% and C-Weighed better than 0.0009%.In-band A-Weighed is better than 0.0012%, C-Weighed better than 0.0009% again.All measurements have been done at the end of 2m interlinks, the input impedance of the analyser set to 100K. This gives the real honest figures going directly into your power amplifier.

In addition to the above, all in-band harmonics stay under –110dB, and out of band residuals at an equal distance to the sample rate of the test tone can be seen at –95dB (like for a 44100 base sample rate and 1000Hz test tone, at 43100 and 45100). When extrapolated from the 24/192000 measurements to the 24/706500 real life playback practice, the figures will be -122dB and -107dB respectively.

Suitable for 110-130V or 220-240V.Watch out : Units with a Serial Number of 10001 u/i 10200 will be internally wired for 110-130V or 220-240V on your indication at ordering. It will need the change of this wireing to make the unit suitable for that other mains. Please take good notice of this when taking (or selling) the unit to country with this other mains;The re-wireing will take 5 minutes to change, but you may not be able to do it yourself. Units with Serial Numbers of 10201 and up will contain a user-switchable power inlet. And careful : The currently used power inlet looks to be switchable as well, but it really is not !! It will only indicate the target mains on the outside, and while this by itself is user-switchable this should not be done in any occasion, without changing the inernal wireing accordingly !

Double secured with 500mA (1000 for 110V) fuses (non “audiophile” for hot and cold); The second fuse is not a spare, but actually used.No mains filter of any kind is applied.

Full color touch display which can be switched off. (Touch) Functionalities vary per XXHighEnd version.

Price of the new NOS1 USB in standard blue colour powdercoat (see below picture) 2ch RCA+XLR Out : 3320 euro ex vat and shipping.Price of Upgrade from the original NOS1 to NOS1 USB : 335 euro ex vat and shipping.

Price of any car paint (two component) colour (provide a colour code please) : 160 euro.Price of powdercoat black (picture at the top) : depending on the amount which can be done at the same time, between 125-175 euro. 70 euro. Edit September 23 2011 : We have let done a batch of 25 for the time being allowing this price now. We name it Saturn Black and it is a soft-feeling beautiful finish with small spikes of metallic.

Notice that the first batch of NOS1 DACs do not contain the DC Offset Control and real time Meters; it is adviced to have your NOS1 upgraded to that for 140 euro, when you upgrade anyway.

Price of further extensions on request (because of the efficiency in the various combinations).Email requests or questions may be sent to sales a@t phasure.com; please denote "NOS1 USB" as part of the title.

No Praphan, of course you don't have to wait. And yes, this is the upgrade.

As a matter of fact, I didn't get around to notify anyone yet, except for one ...Apologizes for that. Anyway, nobody who already ordered will have to wait. This includes your special case. I hope to send you (and everybody) an email later today.

Hi Peter, I'm just off to catch a plane, but I simply HAD to comment on this first. Please reserve two USB upgrades for my two beautiful 'off-white' NOS1s. I'm back in the country on the 23rd, and my NOS1s will be on their way to you on the 25th.

This is very, very exciting stuff.

I have a quick question for you though: Where on Earth do you find the time to do all this stuff? Whatever 'efficiency pills' you take, I want some!

Peter, I am looking forward to hear the new Phasure when Praphan has it installed in his system.I am curious about support for DSD. Is that means that perhaps in the future XXHighend may alsosupport DSD streaming? Also does Phasure support DSD natively or does it convert DSD to PCM first?

I should be getting the new USB module for my PD MPS-5 which will support 24/354 and DSD2 streamingin the next month or so. It would be interesting to compare to Phasure. However, I am running outof input on my LAMM pre with 2 phono pre and one DAC already .

PS is the power cord attachment still in the same location as the original Phasure?

Paul, consider that colour change. You can always tell your wife that this is *the* opportunity to change the colour. Let her pick it, but be careful.

Leo, it is almost not feaseable to wait for it. Theoretically doable but the planning is a bit difficult at this moment. In either case it will take 4 weeks or more to even start thinking about it. Here too, let's continue via email.

Suteetat, as you will have heard we're fighting some stupid double customs duties. Really crazy that there doesn't seem to be a procedure for it. But undoubtedly we will manage.It is the intention that DSD is going to work without conversion to PCM, but honestly I am working on that one right now and the design is not complete yet.Power cord is still the same, but the end of the current stock of cases comes in sight. All is solved by a 90 degree angled cord of course, which anywone can or will do, once you're into your own cords anyway. But notice that this too is "in-DAC" impeded, and where before with XLR a slight rise was to be seen under 100 Hz, today this has completely vanished. IOW, where people might think this is because of 50 (or 60) Hz mains influences, it really is not. Or, not from there at the outside ...

Nick, consider your efforts to be beneficial to all, hence the new NOS1. The latter above is just part of it. I think we have been driving eachother to the sort of ultimate. At least I have been tempted to "see" the least noise possible, which is -as often- only the reference of what's achieveable. Next it "only takes" to push yourself to achieve that reference in whatever other situation. This is what happened, and it is exactly this why USB started to work in the first place. Without this ? no way it would have been any good.For others ... what this came down to in the end to was a design with the least different number of voltages, so no (noise incurring) regulations anywhere had to be applied. This succeeded, although 2 very low current and harmless 1.2 and 2 voltages are still in there. And for your fun Nick : at the very very end (only last Friday) at assembling a first final DAC in this setup, we ran into a small problem I didn't (and actually couldn't) notice myself. A 12V relais which was fed by the old Juli@ 12V linear supply which I still had in my own test DAC. No 12V supply is in the NOS1 USB anymore, and with the solder on the iron we "dicovered" it. A larger problem you can imagine, because no low voltage relais exist for the thicker supply wires it controls (well, not that I could find in fast fashion). I really saw all collapsing, also knowing that no real space is available for another dedicated PSU. But after sitting back for a day I found a solution ...Thank you Nick, on behalf of all.

The Phasure NOS1 24/768 async USB D/A Converter again defines new standards. Not only the technical level is up to the extreme, but sonically it superceeds the original Phasure NOS1 by far. -Unquote-

Hi Peter,

now I'm really confused. I remember the posts about your reservations against USB.-----------------------------------------No USB 3.0 interface?-----------------------------------------"but sonically it superceeds the original Phasure NOS1 by far" - How far? Do I recognize the files (music) or do I hear them with new details?-----------------------------------------

My reservations about USB appeared justified allright because this really won't go by itself. The "problems" themselves didn't change, but my approach did. It is fair to summarize it with two main aspects :

1. Noise which is like (relatively) crazy;2. Jitter which is higher.

Both are related, because at these speeds (480mbs) no means exist to surpress noise other than incurring for additional jitter. Notice that this is not about audible noise as such (around 2mV), but it influences the sonics heavily (well, listening to the NOS1).And so I sat down to achieve the 7-8uV from the original NOS1, which again just has been a reference, or IOW "see, that is possible !".This whole little "project" is about prooving where actually "noise" comes from, and it is here where Nick has been a great help. Not only about looking for even better sonic qualities, but merely about the proof what did NOT help, hence what it all was NOT about. Funnily enough we both worked with the same sources, but onto different applications : Nick with batteries on the Juli@ department, and me with batteries on the USB stuff. We started with this at the same time, but I didn't want to apply it to the Juli@ interface anymore because it seemed the wrong traject. In the mean time though, Nick's sound improved while mine only got worse. It didn't work out, or at least we couldn't find the consistency in it all. I couldn't and Nick couldn't either, both working on a complete diffrerent interface. But here too only one thing seemed important : eliminating all the regulators to be found. Nick's 1, 2, 3, 4 and 5. Maybe 6.I worked out a complete battery operated design (so, 100% of the DAC including chargers of different types for the different types of batteries, the connections), but noticing the inconveniency of charging (though the whole thing could kept on playing for 48 hours continuously) made me work in the other direction more : achieve noise levels with normal PSUs.

A real strange coorporation which merely looked like sparring to me, but -and I can't say this enough- which for me was about "seeing" the reference, thus knowing what must be achieveable.And so the USB interface ended up with 7uV (6uV maybe, depending on the soldering quality), even lower than with the Juli@ interface. Notice though that this isn't about noise at the outputs only, but more importantly about jitter influence which doesn't show as noise at the outputs at all. However, the theories were applied throughout, and while I can't let show jitter of any kind anyway, the sonics told me sufficiently it helped, as it did with Nick's. Measurable or not, the jitter must be way lower now because of the crazy difference in sound. Fun is and remains : no difference with Nick, although working on the complete different interface - and keep in mind, the exact same DAC.

Will you recognize your music ? I guess so. But somehow you won't recognize your listening room ? What you will not recognize is the basses. Not only the upright ones (they are just live now) but also the stiffness of electric ones. Oh, that already was so good ? well, it could be better. This too is just jitter again, no matter how low it is or was.

USB3 ? I wouldn't know why. There's 8x 32/384 (24/384 output) and it really is enough. It would only allow 8x 32/768 as an addition, but more has to change because the on-board processing will have ran out of bandwidth then. Also, keeping in mind this is all meant to be an 8ch XOver, 768 will be too much for everything. Well, that's what I estimate.

September/October ? yes, there should be sufficient stock then. And if not I'll have reordered.

Nick, consider your efforts to be beneficial to all, hence the new NOS1. The latter above is just part of it. I think we have been driving eachother to the sort of ultimate. At least I have been tempted to "see" the least noise possible, which is -as often- only the reference of what's achieveable. Next it "only takes" to push yourself to achieve that reference in whatever other situation. This is what happened, and it is exactly this why USB started to work in the first place. Without this ? no way it would have been any good.

Peter,

Thanks for your kind words,

The fun for me has been that as I was trying to sweat a little extra performance from the Juli@ interface, you were working on similar design decisions on your entirely new interface. So we have had some fun conversations about clock power supplies, regulators, and various low noise supplies.

I want everyone to be in no doubt though that our conversations really touched only on aspects of tuning your new interface. From what I know the new interface you have come up with is truly inspired in its conception and daring in it’s execution. I just don’t know how you do it, but I am very glad you do. I cannot wait to give it a try.

With the knowledge of XXHighEnd and SQ control, together with the development experience of the original NOS1 - at last it was achieved that the software influence has been eliminated. SQ Controls in XXHighEnd won't do a thing to the sonic performance of the new NOS1, as won't different software sound different anymore...

But do different PCs running XXHighEnd sound different? Is it now acceptable to use a laptop? I'm assuming that if the influence of the SW has been eliminated then the influence of the HW has been eliminated also... no?

I ask this because a friend of mine is very interested in buying a NOS1 but would really like to use a laptop, not a desktop, in his main room.

Let me put it like this :You (Mani) have the experience with an Atom based system, right ? or maybe even a latop, I don't know;Now tell me, would you like to use it ?

The story -by now- is too complicated to explain, but maybe it is better to look at 0.9z-6 and how that works. Then you will understand that you still need "the software" first to next be able to eliminate the "controls".Maybe it isn't even right to say that the software stopped influencing "at last", but it does after first running the software in "that mode" (in 0.9z-5 nothing of that is in there).

Think of this stupid (completely made up) example :Suppose your only option would be to use your system in a not bit perfect fashion. Like XP without special drivers always keeps on dithering. Now, XX could have been made so that it can change the dither means. So, you could influence sound by that. Next comes a version along that allows for bit perfect playback forever. And now the dither control obviously can go ...

It is also (for me) a psychological thing (hey Mani, for you too, I know); At first with USB I *needed* all the controls I could find to improve on the bad sound. It helped, but if one thing was right, the other was not. Not much different from what we all experience, no matter what DAC we use. This inherently prooves that something is wrong in the first place, but stil the controls could (would) help. This is where my ever espression came from : when your DAC is not 100% right, you can always influence the sound of it. Well, now it had to be the other way around ... how to get the DAC 100% (??) right, so the controls can go.But the trick is ... both are the same properties. -> Find that major "control" and next fix that. This still needs that control hence the software. In the mean time though the DAC is "100%" also, but now the environment can still destroy (noise). And besides, which those "??" because it won't be 100%. This is where the influence remains.

Riddles ? voodoo again ?Let's see ourselves.

Peter

PS: Also look at my sig and current settings. Quite the opposite of KS Special Mode Ultra Low Latency, right ? That's because I now turned it into a least demanding system. I mean, why not, if it doesn't influence SQ anymore anyway.

You (Mani) have the experience with an Atom based system, right ? or maybe even a latop, I don't know; Now tell me, would you like to use it ?

Yes I have experience with both. I'd happily use either, especially if "less demanding" system settings help. However, it would have to be silent (unnoticeable from listening position) and not take forever to do things in XXHighEnd (such as process flac files). But if the latter hasn't changed, then an Atom would be out, but a powerful laptop might be OK... BUT only if the SQ was not compromised in any way, shape or form.

The story -by now- is too complicated to explain, but maybe it is better to look at 0.9z-6 and how that works. Then you will understand that you still need "the software" first to next be able to eliminate the "controls".

Anyway, it'll be easy for me to try an Atom/laptop for myself when I have 0.9z-6 and the NOS1 USB upgrades done. But just to make things clear, I'm perfectly happy with my current PCs - I'm just trying to find a way of making the NOS1 more compelling for my friend, who is less willing to 'ruin' his beautiful living space for an obsession with sound.

Anybody heard the latest and greatest all that NOS1 USB version in their own system who can comment on its performance versus the previous version which appeared to be a bit sterile sounding for many? Thanks.

Unless you receive private emails from people with contents I don't know about, where do you get this "sterile" from ??I don't recall this was written in here somewhere. Maybe elsewhere though (link ?).

Of course "sterile" can be the or your interpretation of super clean or something, which is what I myself maybe dedicate to the original NOS1, and what sure could be people's perception. But all is relative ... The NOS1-USB is outrageously "clean", but in a way which can't be made clear "anymore". I say it like this because it is beyond understanding. For example about the old recordings which may sound dirty, the original NOS1 really making something of them, but the USB version shows what's really happening. And suddenly no dirt or anything exists anymore. It must be all about the brain; old recordings carry old technique of doing it, and once the brain understands it doesn't hurt. At all !It really is very strange, and as I said elsewhere, it needs other phenomena than we currently know of to describe this.

With the perceived "sterile" (which really sounds as a negative to me), there was this superb accuracy. It seems to go along, right ? Well, it does not. Not if you listen to the NOS1-USB. There's accuracy beyond accuracy, because now, no matter what, you will be unable to detect what's actually wrong with any music, unless ... -watch out- unless it is about a wrongly digitized transfer. You can now just hear what is wrong with it, and where it is wrong. Strangely enough (but actually not) this only happens (doesn't sound good) to those poorly done remasters. This wasn't before at all.

Because this accuracy has impact on everything, the whole perceivement is radically changed. This already was so for the original NOS1, but it is the more so for the NOS1-USB. So, basses change again more to real basses, and for example, now you really can hear the exposure an electric bass has (from its full body wood cabinet). I think this might be *the* example of how again more accuracy can dig up details which seemed impossible before. And let me add to it that all the added detail I perceive myself lately is hardly in the highs - something which seems to be prone for perceiving accuracy in the first place. But to my findings, at some stage this is behind you and further inherent improvements won't exhibit there anymore (except for the impossibility to hear distortions). Instead it sneaks into everything, and in the end "accuracy" exhibits as more natural representation. So, it changed from a technical merit into a functional one.

David, I know you didn't ask for all this, but a couple of weeks further I learn myself as well. It just needs a post like yours to tell about it a little ...

Except for one, nobody really knows - but during the stage of getting the first NOS1 shipped a few things happened ...

I'm talking about the day I created this very thread, being confident that all was good to go. Ok, not enough stock to really satisfy all soon, but I knew that and I told about it.The first NOS1-USB really was completely ready; it was measured and everything, and we were about to book it for shipment. But suddenly there came a message from someone (haha) owning two NOS1's, and both exhibited the same offset change, going from day one to day two. This combined with other experiences, and I said to myself, till here and no further. The story is much longer, and in the end is related to our mains systems and house grounding. Never mind this for now. But I wanted to definitely solve it. And not to forget : NOT by means of something in the signal path ... (how difficult can one make it for himself ).

After a search of two full weeks - soldering in and out and back again, SMD stuff and chips and everything - I was as far as two sections on the gain stage possibly influcencing eachother in an illegal way (not that electronics or simulations could proove that), that impeded by whatever groundloops coming from external.In the mean time, we already found that we were able to create the offset just by hovering the NOS1 like reaching for switching it on ... However, one person could incur for that, and the other could not. The difference was in the shoes (isolating rubber vs. not isolating). Ok, it's not a strange story by itself that "we" guide current to earth, but part of the long story is that once a ground loop is setup like this, you can't get rid of it anymore. So, it is you who incur for the loop, but the loop goes through the DAC and stays. This is all in very brief ...

After tearing down really every part of that new NOS1-USB we expected a possible culprit to be in two "fighting" parts of the gain stage, and so I set myself to eliminate those two parts into one only; no fight possible with one part.Well, in the spirit of Nick's activities again, this part which could be eliminated is a part which creates 2.5V out of 5V. This is a shunt regulated section consisting of some chips and transistors, and if you think of how a "shunt" operates, yes, this is prone to misery (you can't even see that things go wrong because of the ever the same voltage and actually same current flowing).Of course the transfer to 2.5V was there for a reason, so that reason had to be changed / eliminated.In brief again, I managed. Took days of reading datasheets at finding the suitable parts, preferrably all fitting the existing PCB or otherwise hell would break loose on redesigning that - reproducing that (preferrably in test first) - waiting for all that. But this turned out not to be necessary.

As Nick will know, I already was hunting for letting all run on exactly one voltage only, and this is exactly what is happening at this moment. And the big fun : the 7-8uV output noise has decreased to the 6uV range. Haha.I know, people declare me crazy, but since I'm saying that noise rides ON the signal, and is not under it, it must be a good thing. And in the end you could say that there's 15% less output noise now, which seems a large figure to me.I'm 100% sure it is audible as well, and at some strange "level" new details pop up. This is so audible that my partner in crime here told me that distortion was exhibiting from a certain familiar track, while really it is in the music itself (and no distortion, but a very fast on/off synthesized sound). So, things look to be faster once again. Btw, an example would be the Mini Moog from Rick Wakeman on Journey to the Center of The Earth and the higher pitched tones. This now is pure on/off sound, while at first it merely was a fluent synth sound.

The mechanism to avoid the ground loop -which is that 140 euro upgrade- actually can go now. Also for the 110V systems where it was created for. However, it will stay in, because in the mean time it's a provision to keep the PSU "hot" while the DAC section is (can be) shut off.Also nice to know may be the fact that the rails for the output stage now indeed is +/- 5V while 2.1V (+/-) only is needed, and although before there was 0.4V headroom on the 2.5V rails (for overshoots) now there's headroom which never will be utilized.

In the mean time we are out of other stock, this time on ready gain stage PCBs. Well, that happens when you prepare a bunch while afterwards they need to be changed. At least today all the new parts for it will arrive, but it remains a little set back at changing the existing ones, which is a necessity because we're out of fresh PCBs. Wat a laugh.

All 'n all it has been taken longer than planned to get this really rolling, but at least I am glad that no single NOS1-USB has left with "older specs". In the mean time a possible DC Offset problem (wearing around in two ghost hunted English houses with a leakage to one in Norway) now is history. I sure am glad about that.

In the mean time a possible DC Offset problem (wearing around in two ghost hunted English houses with a leakage to one in Norway) now is history.

Yeah, my Victorian ghosts told me they like travelling to more Northern climbs when the weather gets too hot here (not very often, of course). But I'm glad it's all sorted out now as they were getting fed up of all my accusations of what they did to my NOS1s when I was away.

Anyway, really nice story Peter. And as I've said in a PM, there's absolutely no rush on my part - I'm actually quite enjoying listening to LPs right now - but I'm very much looking forward to hearing the 'new' NOS1. (BTW, at what point will it become the NOS2?)

Anybody heard the latest and greatest all that NOS1 USB version in their own system who can comment on its performance versus the previous version which appeared to be a bit sterile sounding for many?

earflappin, nice to have you back!

I can see how my first post in the thread http://www.phasure.com/index.php?topic=1549.0 might be interpreted as the NOS1 sounding 'sterile'. However, I was then using KS Adaptive. It became quite clear that the NOS1 sounded more 'organic' (and better) with KS Special.

Of course, everything in the aforementioned thread relates to the 'original' NOS1. As soon as I get hold of a 24/768 async USB NOS1 (not sure how long this will take), I'll let you know what I think...

Mani, thanks for the welcome back and willingness to share your experiences with the new NOS1 USB upgrade. I am very much looking forward to it.

Peter, my apologies if the word "sterile" offended. It was not my intent! It was not a word I had seen posted in NOS1 reviews, but one I used based on the comments I had read. I was looking for a single word that kind of summed up what I had read. I agree this word is generally considered a negative. I mean who says, "yes, I'm looking for the most sterile sounding DAC I can"! Going back and reading the reviews more carefully I can see this is not the essence of what was written. Clean, clear, resolute....yes, but not lacking musicality.

In any case I am anxiously waiting for the NOS1 USB reviews. I'm still running a Mac Mini (oh blasphemy you say - but I can run Fusion on it of course) as music server with Fidelia (the best Mac-based player I've heard) and running async Firewire to my Metric Halo LIO-8. The best digital I've heard in my system to date. I also am set up to run active or passive crossovers.

BTW, someone mentioned about trying a gainclone amp. Let me say that I am running a Class D Audio SDS-224 amp with a discrete linear PSU with a 12ns ultra fast rectifier and Jensen 4 pole caps and this thing is simply amazing. It punches way, way above it's modest price tag and is very easy to build. I know some DIY'ers here in the USA that put it's performance about the gainclones they owned.

David - maybe I should have been the one greeting you explicitly, but I wasn't sure whether it would be received well. But ok, hey, how are you doing !!?

I can tell you, I have been about to post a (stupid) question about what Mac software to use for the NOS1 - just because it needs that "filtering". But as I just saw (CA) you are excited about Fidelia. So, I guess I will go that direction for trials (including the "upsampling" ).

The fact that you just mentioned the Jensen 4 poles makes me even more excited, because I just today decided to go for BHC's (that other 4 pole brand) for something new I'm heading to. Not for their official purpose, but for something new and "exciting".Crazily expensive though (30 euro range pp).

I guess you read this one : Gainclone heaven ?We may all end up in some same boat. But things sure are changing ...

Peter, it's great to reconnect! Thanks for your post. I was away from audio for quite a bit as I had my speakers rebuilt and my system was down, but have periodically checked on your progress with the NOS1.

First, let me say congratulations on bringing the NOS1 to market. This was a HUGE undertaking. I don't think most people appreciate the complexity of designing a DAC from the ground up. I honestly wondered (only sometimes ) if you would make it, but my sense was that you had the passion, determination, smarts and understanding spouse! to make it happen. I can't wait to try one. I guess I need to read up on the process for ordering one. What's your ship time like these days?

Yes, after comparing Pure Music, Audirvana and Fidelia I would rate Fidelia as a clear step ahead of the others in terms of PRaT - it just sounds more like live music. I'm not that surprised as the designers are music guys first and software people second. I'm not sure how good their real-time upsampling capability is as I don't use it. I'm pleased that there will be a native Mac player that will work with the NOS1 and that should increase your available market as well.

Regarding the gainclone, I read the thread you posted. Interesting. Below is a link to a review from a guy named "posideonsvoice" who is an accomplished DIY'er who built the Class D Audio SDS amp I referred to and who had previously used a gainclone as his main amp.

Hi Peter, just wondering if you did any testing regarding the length and quality of the usb cable between the NOS USB and the computer. With my old setup, JKenny USB/SPDIF converter to MSB DAC, the length of the cable made a very significant difference. Thanks.

USB3 ? I wouldn't know why. There's 8x 32/384 (24/384 output) and it really is enough. It would only allow 8x 32/768 as an addition, but more has to change because the on-board processing will have ran out of bandwidth then. Also, keeping in mind this is all meant to be an 8ch XOver, 768 will be too much for everything. Well, that's what I estimate.

Hi Peter, just wondering if you did any testing regarding the length and quality of the usb cable between the NOS USB and the computer. With my old setup, JKenny USB/SPDIF converter to MSB DAC, the length of the cable made a very significant difference. Thanks.

Hey you ...

I am using 20' (6 meters) of it right now. This distance to the iMac here.hahaMore won't work.

Shifting gears for a moment here, I remember reading juanpmar's excellent posts on building a PC for XXHighEnd. My understanding now is that the asynchronous DAC does not make the same demands on the PC that the previous DAC version did. What does this mean for the listener looking to build a silent audiophile server to keep in the same room as the NOS 1? Is an atom-based system with less RAM feasible for use with the Phasure or should one still look to an Intel Sandy Bridge CPU with 8Gb of RAM? Is a 2010 mac mini acceptable with Audirvana and, alternatively, can you run XXHighEnd acceptably on a mac mini partition running Windows 7(?Premium/Professional/Ultimate)? Is Chris Connaker's Computer Audiophile c.a.p.s. v. 2.0 server an acceptable option for the async Phasure NOS? I know, questions and more questions for Peter in his non-spare time spare time(as we say in America).

All you mention will run without problems. But what remains is the load on the "PC". One can well say that the more the relative (to the capacity) load is, the less the sonical outcome will be. If you, by the time, have two machines hanging around (prefarrably two Macs or two PCs), you can easily determine whether there's a difference. If there is, we always can see further, or ?

Karma, you're going to find it pretty difficult connecting a CD transport to a NOS1. The original NOS1 needs a computer with a PCIe slot and the new USB NOS1 needs... you've guessed it... a USB connection. I don't know of a CD transport that has a USB connection as an output.

You can always use the computer's CD-ROM drive to play CDs of course. You can't do this with XXHighEnd, but something like HQPlayer would work fine. I've never tried this and have no idea how it would sound. I'm travelling for work at the moment but am happy to try this when I get back if you like. Though I strongly suspect your question was aimed at eliminating a computer altogether... Can't be done, as far as I know.

Karma, you're going to find it pretty difficult connecting a CD transport to a NOS1. The original NOS1 needs a computer with a PCIe slot and the new USB NOS1 needs... you've guessed it... a USB connection. I don't know of a CD transport that has a USB connection as an output.snipI'm travelling for work at the moment but am happy to try this when I get back if you like. Though I strongly suspect your question was aimed at eliminating a computer altogether... Can't be done, as far as I know.

Cheers, Mani.

Cheers Mani,That would be swell. Thank you for being the PR for Peter I am here at Peter's cos of you.

New habits diehard. I have been a CAS user for more than 7 years - perhaps??? With my DAC202 I was completely fedup and went digital. Hence my mind is still on CAS/Digital mode. Sure I can go back to CAS again, specially as this new special DAC is here! (Deja Vu? Had said the same before hearing, pushing down the cheque for the DAC202).

I spy another PC board on the DAC, can this accept any digital signal via suitable PC card? I wonder what the Hardware can do for the CDP? Perhaps tons - despite what I read about the digital filter,software side and the interface at the devils lair, I still read that the sound gets crazy after a suitable burn in. Hence teh CDP connection also sounds promising...

What people don't know is that I have an extended version of the NOS1-USB specs as well. This lists a few other possibilities, but it gold wild and I provided a simple one.

Think like about everything is possible, until we run out of input/output terminals (there are 12 possible in total with this cabinet). However, everything has to be created specifically for that first time, plus -and this is important- it will imply a load on the driver which is not preferrable. Not the most big deal, because I can provide as many driver versions as we need, and you could have one for normal playback, and another for ... well, playback from a transport via SPDIF-In. Of course, when you in ad-hoc fashion want to play a CD from the CDP this is not the most convenient, although uninstalling and re-installing takes maybe 2 minutes all together. But still, I think you'd *have* to do that for optimum sonic performance (without this latter one more general driver version will support more in one go).

I must also admit that I have been reluctant to tell about further options, because it will presumeably take ages of emails when not put out in the open to begin with, and/but no elementary option can have a standard price anyway because of a. efficieny in combinations and/or b. additional complexity because of the bunch of wires to solder it will take in the small space. Not working by "standards" also has its price.

By now, things having cooled down a bit, I may be up to it all, but the time it will take to really sort out things for the first time (because that is what it will be), is to be subtracted from the total capacity we have here, and which for sure at this time is not infinite (regarding the already too long pending orders).

Anyway, SPDIF-In is normally possible (not AES and no BNC connectors without further search for Neutrik fit), but at this time I don't even know what the maximum samle rate will be. Like for SPDIF-Out (also possible) this is 24/96, but which may well become 24/192 later.

Additional "complexity" arrives when we see that SPDIF-In can go via an internal SRC, or just without. Again driver settable, and don't ask me about the merits at this time.

Let's assume that such a connection takes 200 euros, then maybe you say "never mind". Good for me. But also note, please, that when this "first" costs 200 euros, a next may cost 50 euros because the main work has been spent ... as it can also cost 300 euros later because we then know what's really to be done. So, a vague thing at first always, and next there's this combination with other stuff.

It also can well be that we'll provide a few combination settings only. You know, those where you will be paying more than you asked for, but which makes life easier on our side.

Ok, I just scratched another of these more too wild possibilities, and actually I can't hold up. But I do for now anyway. But to keep in mind at all times : any of these options will come across as overpriced (mainly because of the driver work and sustaining the best SQ for the specific situation).

I'd say : When people have specific questions, let's ask them in this topic, which at least prevents from answering all the emails.

What people don't know is that I have an extended version of the NOS1-USB specs as well. This lists a few other possibilities, but it gold wild and I provided a simple one.snipThink like about everything is possible, until we run out of input/output terminals (there are 12 possible in total with this cabinet). Regards,Peter

Thanks DACtor PETERUnderstood about the cost escalation and the incrimental, morphological, possibilities of this creation of yours. As Mani noted he will try, so will ; When I get my hands on your unit.

I am now waiting for your payment call and delivery date (sigh!!!6wks. )

Hope all is well. Sounds like the last show was a success! How did the Ferrari Red DAC turn out? Would love to see pictures. If Heaven smiles on us and we have some $$ to play with, I would love to get one of your DACS. If you make it back to the US, please look us up.